@Hugo: I am assuming that by "classical misconception" you mean that the species don't really replace each other as the drawing suggests, but that they fork into new evolutionary lines - with antecedents remaining "behind" as new species.The ascent of man is a work of art that overly simplifies the darwinian tree and is probably partially to blame for the "we come from monkeys" argument. My design is a further simplification of the original art because the stick figures kinda remind me of a broken up darwinian tree. I actually traced the joints of each figure in that drawing. Primarily the reason was pain avoidance, survival of the wimpiest. I had no intention of enduring the pain required to etch each figure in detail.Please feel free to clarify your comment if I assumed wrong.